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Updated: May 18, 2026
A Precise Pathogen Delivery and Recovery System for Murine Models of Secondary Bacterial Pneumonia
Published on: September 21, 2019
Profiling microRNAs in lung tissue from pigs infected with Actinobacillus pleuropneumoniae
Agnieszka Podolska1, Christian Anthon, Mads Bak
1Department of Veterinary Clinical and Animal Sciences, Section of Anatomy, Cell Biology, Genetics and Bioinformatics, University of Copenhagen, Faculty of Health and Medical Sciences, Copenhagen, Denmark.
Background:
MicroRNAs (miRNAs) are a class of non-protein-coding genes that play a crucial regulatory role in mammalian development and disease. Whereas a large number of miRNAs have been annotated at the structural level during the latest years, functional annotation is sparse. Actinobacillus pleuropneumoniae (APP) causes serious lung infections in pigs. Severe damage to the lungs, in many cases deadly, is caused by toxins released by the bacterium and to some degree by host mediated tissue damage. However, understanding of the role of microRNAs in the course of this infectious disease in porcine is still very limited.
Results:
In this study, the RNA extracted from visually unaffected and necrotic tissue from pigs infected with Actinobacillus pleuropneumoniae was subjected to small RNA deep sequencing. We identified 169 conserved and 11 candidate novel microRNAs in the pig. Of these, 17 were significantly up-regulated in the necrotic sample and 12 were down-regulated. The expression analysis of a number of candidates revealed microRNAs of potential importance in the innate immune response. MiR-155, a known key player in inflammation, was found expressed in both samples. Moreover, miR-664-5p, miR-451 and miR-15a appear as very promising candidates for microRNAs involved in response to pathogen infection.
Conclusions:
This is the first study revealing significant differences in composition and expression profiles of miRNAs in lungs infected with a bacterial pathogen. Our results extend annotation of microRNA in pig and provide insight into the role of a number of microRNAs in regulation of bacteria induced immune and inflammatory response in porcine lung.
Insights
This study identifies microRNAs (miRNAs) in pigs affected by Actinobacillus pleuropneumoniae lung infections. It reveals significant differences in miRNA expression, highlighting potential roles in the immune response to bacterial pathogens.
Area of Science:
- Veterinary Science
- Molecular Biology
- Immunology
Background:
- MicroRNAs (miRNAs) are crucial regulators in mammalian development and disease, but their functions in porcine infectious diseases are poorly understood.
- Actinobacillus pleuropneumoniae (APP) causes severe, often fatal, lung infections in pigs, with limited knowledge of the host's microRNA involvement.
- Understanding miRNA roles in APP infection is vital for developing new therapeutic strategies.
Purpose of the Study:
- To investigate the role of microRNAs in porcine lung tissue during Actinobacillus pleuropneumoniae infection.
- To identify and characterize differentially expressed miRNAs in response to bacterial infection.
- To provide insights into the host's immune and inflammatory responses at the molecular level.
Main Methods:
- Small RNA deep sequencing was performed on unaffected and necrotic lung tissues from pigs infected with APP.
- Identification of conserved and novel microRNAs in porcine lung tissue.
- Differential expression analysis of identified microRNAs.
Main Results:
- 169 conserved and 11 novel microRNAs were identified in the pig.
- Significant differential expression of miRNAs was observed, with 17 up-regulated and 12 down-regulated in necrotic tissue.
- Specific miRNAs, including miR-155, miR-664-5p, miR-451, and miR-15a, were highlighted for their potential roles in the innate immune response to bacterial infection.
Conclusions:
- This study presents the first evidence of altered miRNA profiles in porcine lungs infected with a bacterial pathogen.
- The findings expand the annotation of porcine miRNAs and offer insights into their regulatory functions in bacterial-induced immune and inflammatory responses.
- The identified miRNAs represent potential biomarkers and therapeutic targets for Actinobacillus pleuropneumoniae infections.
